This application relates generally to communication systems, and, more particularly, to wireless communication systems.
Wireless communication systems provide wireless connectivity to access terminals using a network of interconnected access nodes or base stations. Communication over the air interface between the access terminals and the base stations takes place according to various agreed-upon standards and/or protocols. For example, the Third Generation Partnership Project (3GPP, 3GPP2) has specified a set of standards for a packet-switched wireless communication system referred to as Long Term Evolution (LTE). The LTE standards support downlink transmission using orthogonal frequency division multiplexing (OFDM). Access terminals (such as base stations or eNodeBs) can concurrently communicate with multiple users over control and data channels formed by allocating symbols in different sets of non-overlapping Fourier-coefficients or sub-carriers. The LTE standards also support multiple-input/multiple-output (MIMO) communication over the air interface using multiple antennas deployed at transmitters and/or receivers. The carrier bandwidth supported by LTE is approximately 20 MHz, which can support a downlink peak data rate of approximately 100 Mbps and a peak data rate of the uplink of approximately 50 Mbps.
The LTE standards also support coordinated multipoint (CoMP) transmission techniques including dynamic point selection (DPS) or joint transmission (JT). Coordinated multipoint transmissions for user equipment are coordinated by the serving cell for the user equipment using information communicated between the serving cell and other neighboring cells that are participating in the coordinated transmission. The serving cell can then schedule downlink transmissions to user equipment, e.g., based on channel conditions between the user equipment, the serving cell, and the neighboring cells. In dynamic point selection, the serving cell can schedule transmissions by the neighboring cells for different subframes one cell at a time. In joint transmission, the serving cell schedules concurrent transmissions by multiple cells, which may or may not include the serving cell.